Exclude ProxyAuthOnUserBoardScreenTest.ProxyAuthDialogOnUserBoardScreen/1 under MSan

chrome/browser/chromeos/login/proxy_auth_dialog_browsertest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/login_manager_test.h"
@@ skipping 110 matching lines @@
                                        "$('add-user-button').click()"
                                        "));"));
     screen_waiter.Wait();
     auth_dialog_waiter.Wait();
     ASSERT_TRUE(auth_dialog_waiter.login_handler());
   }
 }
 
 INSTANTIATE_TEST_CASE_P(ProxyAuthOnUserBoardScreenTestSuite,
                         ProxyAuthOnUserBoardScreenTest,
+// Times out under MSan: https://crbug.com/481651
+#if defined(MEMORY_SANITIZER)
+                        testing::Values(false));
+#else
                         testing::Bool());
+#endif
 
 }  // namespace chromeos